# Provenance backfill

Purpose
- Backfill missing provenance records with deterministic ordering.

Inputs
- Attestation inventory (NDJSON) with subject and digest data.
- Subject to Rekor map for resolving transparency entries.

Procedure
1. Validate inventory records (UUID or ULID and digest formats).
2. Resolve each subject to a Rekor entry; record gaps and skip if missing.
3. Emit backfilled provenance events using a backfill mode that preserves ordering.
4. Log every backfilled subject and Rekor digest pair as NDJSON.
5. Repeat until gaps are zero and record completion in audit logs.

Determinism
- Sort by subject then Rekor entry before processing.
- Use canonical JSON writers and UTC timestamps.

Related references
- provenance/inline-provenance.md
- provenance/attestation-workflow.md
- docs/provenance/prov-backfill-plan.md